此篇文章为转载,原文地址 http://blog.csdn.net/zhibudefeng/article/details/8463268;
- (void)drawRect:(CGRect)rect{ CGContextRef context = UIGraphicsGetCurrentContext(); /*NO.1画一条线 CGContextSetRGBStrokeColor(context, 0.5, 0.5, 0.5, 0.5);//线条颜色 CGContextMoveToPoint(context, 20, 20); CGContextAddLineToPoint(context, 200,20); CGContextStrokePath(context); */ /*NO.2写文字 CGContextSetLineWidth(context, 1.0); CGContextSetRGBFillColor (context, 0.5, 0.5, 0.5, 0.5); UIFont *font = [UIFont boldSystemFontOfSize:18.0]; [@"公司:北京中软科技股份有限公司\n部门:ERP事业部\n姓名:McLiang" drawInRect:CGRectMake(20, 40, 280, 300) withFont:font]; */ /*NO.3画一个正方形图形 没有边框 CGContextSetRGBFillColor(context, 0, 0.25, 0, 0.5); CGContextFillRect(context, CGRectMake(2, 2, 270, 270)); CGContextStrokePath(context); */ /*NO.4画正方形边框 CGContextSetRGBStrokeColor(context, 0.5, 0.5, 0.5, 0.5);//线条颜色 CGContextSetLineWidth(context, 2.0); CGContextAddRect(context, CGRectMake(2, 2, 270, 270)); CGContextStrokePath(context); */ /*NO.5画方形背景颜色 CGContextTranslateCTM(context, 0.0f, self.bounds.size.height); CGContextScaleCTM(context, 1.0f, -1.0f); UIGraphicsPushContext(context); CGContextSetLineWidth(context,320); CGContextSetRGBStrokeColor(context, 250.0/255, 250.0/255, 210.0/255, 1.0); CGContextStrokeRect(context, CGRectMake(0, 0, 320, 460)); UIGraphicsPopContext(); */ /*NO.6椭圆 CGRect aRect= CGRectMake(80, 80, 160, 100); CGContextSetRGBStrokeColor(context, 0.6, 0.9, 0, 1.0); CGContextSetLineWidth(context, 3.0); CGContextAddEllipseInRect(context, aRect); //椭圆 CGContextDrawPath(context, kCGPathStroke); */ /*NO.7 CGContextBeginPath(context); CGContextSetRGBStrokeColor(context, 0, 0, 1, 1); CGContextMoveToPoint(context, 100, 100); CGContextAddArcToPoint(context, 50, 100, 50, 150, 50); CGContextStrokePath(context); */ /*NO.8渐变 CGContextClip(context); CGColorSpaceRef rgb = CGColorSpaceCreateDeviceRGB(); CGFloat colors[] = { 204.0 / 255.0, 224.0 / 255.0, 244.0 / 255.0, 1.00, 29.0 / 255.0, 156.0 / 255.0, 215.0 / 255.0, 1.00, 0.0 / 255.0, 50.0 / 255.0, 126.0 / 255.0, 1.00, }; CGGradientRef gradient = CGGradientCreateWithColorComponents (rgb, colors, NULL, sizeof(colors)/(sizeof(colors[0])*4)); CGColorSpaceRelease(rgb); CGContextDrawLinearGradient(context, gradient,CGPointMake (0.0,0.0) ,CGPointMake(0.0,self.frame.size.height), kCGGradientDrawsBeforeStartLocation); */ /* NO.9四条线画一个正方形 //画线 UIColor *aColor = [UIColor colorWithRed:0 green:1.0 blue:0 alpha:0]; CGContextSetRGBStrokeColor(context, 1.0, 0, 0, 1.0); CGContextSetFillColorWithColor(context, aColor.CGColor); CGContextSetLineWidth(context, 4.0); CGPoint aPoints[5]; aPoints[0] =CGPointMake(60, 60); aPoints[1] =CGPointMake(260, 60); aPoints[2] =CGPointMake(260, 300); aPoints[3] =CGPointMake(60, 300); aPoints[4] =CGPointMake(60, 60); CGContextAddLines(context, aPoints, 5); CGContextDrawPath(context, kCGPathStroke); //开始画线 */ /* NO.10 UIColor *aColor = [UIColor colorWithRed:0 green:1.0 blue:0 alpha:0]; CGContextSetRGBStrokeColor(context, 1.0, 0, 0, 1.0); CGContextSetFillColorWithColor(context, aColor.CGColor); //椭圆 CGRect aRect= CGRectMake(80, 80, 160, 100); CGContextSetRGBStrokeColor(context, 0.6, 0.9, 0, 1.0); CGContextSetLineWidth(context, 3.0); CGContextSetFillColorWithColor(context, aColor.CGColor); CGContextAddRect(context, rect); //矩形 CGContextAddEllipseInRect(context, aRect); //椭圆 CGContextDrawPath(context, kCGPathStroke); */ /* NO.11 画一个实心的圆 CGContextFillEllipseInRect(context, CGRectMake(95, 95, 100.0, 100)); */ /*NO.12 画一个菱形 CGContextSetLineWidth(context, 2.0); CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor); CGContextMoveToPoint(context, 100, 100); CGContextAddLineToPoint(context, 150, 150); CGContextAddLineToPoint(context, 100, 200); CGContextAddLineToPoint(context, 50, 150); CGContextAddLineToPoint(context, 100, 100); CGContextStrokePath(context); */ /*NO.13 画矩形 CGContextSetLineWidth(context, 2.0); CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor); CGRect rectangle = CGRectMake(60,170,200,80); CGContextAddRect(context, rectangle); CGContextStrokePath(context); */ /*椭圆 CGContextSetLineWidth(context, 2.0); CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor); CGRect rectangle = CGRectMake(60,170,200,80); CGContextAddEllipseInRect(context, rectangle); CGContextStrokePath(context); */ /*用红色填充了一段路径: CGContextMoveToPoint(context, 100, 100); CGContextAddLineToPoint(context, 150, 150); CGContextAddLineToPoint(context, 100, 200); CGContextAddLineToPoint(context, 50, 150); CGContextAddLineToPoint(context, 100, 100); CGContextSetFillColorWithColor(context, [UIColor redColor].CGColor); CGContextFillPath(context); */ /*填充一个蓝色边的红色矩形 CGContextSetLineWidth(context, 2.0); CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor); CGRect rectangle = CGRectMake(60,170,200,80); CGContextAddRect(context, rectangle); CGContextStrokePath(context); CGContextSetFillColorWithColor(context, [UIColor redColor].CGColor); CGContextFillRect(context, rectangle); */ /*画弧 //弧线的是通过指定两个切点,还有角度,调用CGContextAddArcToPoint()绘制 CGContextSetLineWidth(context, 2.0); CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor); CGContextMoveToPoint(context, 100, 100); CGContextAddArcToPoint(context, 100,200, 300,200, 100); CGContextStrokePath(context); */ /* 绘制贝兹曲线 //贝兹曲线是通过移动一个起始点,然后通过两个控制点,还有一个中止点,调用CGContextAddCurveToPoint() 函数绘制 CGContextSetLineWidth(context, 2.0); CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor); CGContextMoveToPoint(context, 10, 10); CGContextAddCurveToPoint(context, 0, 50, 300, 250, 300, 400); CGContextStrokePath(context); */ /*绘制二次贝兹曲线 CGContextSetLineWidth(context, 2.0); CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor); CGContextMoveToPoint(context, 10, 200); CGContextAddQuadCurveToPoint(context, 150, 10, 300, 200); CGContextStrokePath(context); */ /*绘制虚线 CGContextSetLineWidth(context, 5.0); CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor); CGFloat dashArray[] = {2,6,4,2}; CGContextSetLineDash(context, 3, dashArray, 4);//跳过3个再画虚线,所以刚开始有6-(3-2)=5个虚点 CGContextMoveToPoint(context, 10, 200); CGContextAddQuadCurveToPoint(context, 150, 10, 300, 200); CGContextStrokePath(context); */ /*绘制图片 NSString* imagePath = [[NSBundle mainBundle] pathForResource:@"dog" ofType:@"png"]; UIImage* myImageObj = [[UIImage alloc] initWithContentsOfFile:imagePath]; //[myImageObj drawAtPoint:CGPointMake(0, 0)]; [myImageObj drawInRect:CGRectMake(0, 0, 320, 480)]; NSString *s = @"我的小狗"; [s drawAtPoint:CGPointMake(100, 0) withFont:[UIFont systemFontOfSize:34.0]]; */ /* NSString *path = [[NSBundle mainBundle] pathForResource:@"dog" ofType:@"png"]; UIImage *img = [UIImage imageWithContentsOfFile:path]; CGImageRef image = img.CGImage; CGContextSaveGState(context); CGRect touchRect = CGRectMake(0, 0, img.size.width, img.size.height); CGContextDrawImage(context, touchRect, image); CGContextRestoreGState(context); */ /*NSString *path = [[NSBundle mainBundle] pathForResource:@"dog" ofType:@"png"]; UIImage *img = [UIImage imageWithContentsOfFile:path]; CGImageRef image = img.CGImage; CGContextSaveGState(context); CGContextRotateCTM(context, M_PI); CGContextTranslateCTM(context, -img.size.width, -img.size.height); CGRect touchRect = CGRectMake(0, 0, img.size.width, img.size.height); CGContextDrawImage(context, touchRect, image); CGContextRestoreGState(context);*/ /* NSString *path = [[NSBundle mainBundle] pathForResource:@"dog" ofType:@"png"]; UIImage *img = [UIImage imageWithContentsOfFile:path]; CGImageRef image = img.CGImage; CGContextSaveGState(context); CGAffineTransform myAffine = CGAffineTransformMakeRotation(M_PI); myAffine = CGAffineTransformTranslate(myAffine, -img.size.width, -img.size.height); CGContextConcatCTM(context, myAffine); CGContextRotateCTM(context, M_PI); CGContextTranslateCTM(context, -img.size.width, -img.size.height); CGRect touchRect = CGRectMake(0, 0, img.size.width, img.size.height); CGContextDrawImage(context, touchRect, image); CGContextRestoreGState(context); */}